In order to get the best landscape value of Browallia speciosa Hook. and Thevetia peruviana (Pers) K. Schum. plants
when used as pot plants the present study was conducted in a semi-shade place at the nursery of Orman Botanical Garden,
Hort. Res. Inst., Giza, Egypt during 2016 and 2017 seasons, where one-year-old seedlings of the aforenamed two plant
species were transplanted in 20-cm-diameter plastic pots filled with about 3.5 kg of one of the following media: pure sand
(as control) or sand supplemented with 25 % (3:1, v/v) of either clay or farmyard manure (FYM). After 2 weeks from
transplanting, the seedlings received 3 fertilization treatments as follows: ammonium sulphate [(NH4)2SO4, 20.5 % N] at 2
g /plant, added monthly as soil drench for 5 times, and 2 forms of potassein [K-N (30 % K2O + 8 % N) and K-P (30 %
K2O + 10 % P2O5)], added monthly for 5 times as foliar spray at 2 ml/l concentration for each. The effect of combined
treatments between growing media and fertilization treatments was also studied.
The results of this study have shown that means of vegetative and root growth parameters (plant length, stem
diameter, No. leaves/plant, root length and fresh and dry weights of leaves and roots) of the two studied plants were
significantly increased in response to amending the sand with 25 % (3:1, v/v) of either clay or FYM, as well fertilizing
with either form of potassein, with the superiority of both sand + 25 % (3:1, v/v) FYM growing media and K-N at 2 ml/l
fertilization treatments, that gave the highest records in the two seasons. Thus, the best growth in both plants was attained
by planting them in sand + 25 % (3:1, v/v) FYM mixture and spraying their foliage with 2 ml/l K-N aqueous solution. A
similar trend was also obtained concerning the leaf content of chlorophyll a, b, carotenoids, N, P and K, with few
exceptions.
So, it can be recommended to planting the one-year-old seedlings of both Browallia speciosa and Thevetia peruviana
in a mixture composed of sand + 25 % (3:1, v/v) FYM and spraying their foliage with aqueous solution of potassein N at 2
ml/l concentration, 5 times with one month interval to get model pot plants of high quality.